{2192} Primeἔχωecho{ekh'-o}A primary verb (including an alternate form σχέω [[scheo]], {skheh'-o}; used in certain tenses only); to hold (used in very various applications, literally or figuratively, direct or remote; such as possession, ability, contiguity, relation or condition).

{1438} Primeἑαυτοῦheautou{heh-ow-too'}(Including all the other cases); from a reflexive pronoun otherwise obsolete and the genitive (dative or accusative) of G0846; him (her, it, them, also [in conjunction with the personal pronoun of the other persons] my, thy, our, your) -self (-selves), etc.

{2532} Primeκαίkai{kahee}Apparently a primary particle, having a copulative and sometimes also a cumulative force; and, also, even, so, then, too, etc.; often used in connection (or composition) with other particles or small words.

1 John 1:8

_ _ The confession of sins is a necessary consequence of “walking in the light” (1 John 1:7). “If thou shalt confess thyself a sinner, the truth is in thee; for the truth is itself light. Not yet has thy life become perfectly light, as sins are still in thee, but yet thou hast already begun to be illuminated, because there is in thee confession of sins” [Augustine].

_ _ that we have no sin  “HAVE,” not “have had,” must refer not to the past sinful life while unconverted, but to the present state wherein believers have sin even still. Observe, “sin” is in the singular; “(confess our) sins” (1 John 1:9) in the plural. Sin refers to the corruption of the old man still present in us, and the stain created by the actual sins flowing from that old nature in us. To confess our need of cleansing from present sin is essential to “walking in the light”; so far is the presence of some sin incompatible with our in the main “walking in light.” But the believer hates, confesses, and longs to be delivered from all sin, which is darkness. “They who defend their sins, will see in the great day whether their sins can defend them.”

_ _ deceive ourselves  We cannot deceive God; we only make ourselves to err from the right path.

_ _ the truth  (1 John 2:4). True faith. “The truth respecting God’s holiness and our sinfulness, which is the very first spark of light in us, has no place in us” [Alford].

1 John 1:8-10

_ _ Here, I. The apostle, having supposed that even those of this heavenly communion have yet their sin, proceeds here to justify that supposition, and this he does by showing the dreadful consequences of denying it, and that in two particulars:  1. If we say, We have no sin, we deceive ourselves, and the truth is not in us,1 John 1:8. We must beware of deceiving ourselves in denying or excusing our sins. The more we see them the more we shall esteem and value the remedy. If we deny them, the truth is not in us, either the truth that is contrary to such denial (we lie in denying our sin), or the truth of religion, is not in us. The Christian religion is the religion of sinners, of such as have sinned, and in whom sin in some measure still dwells. The Christian life is a life of continued repentance, humiliation for and mortification of sin, of continual faith in, thankfulness for, and love to the Redeemer, and hopeful joyful expectation of a day of glorious redemption, in which the believer shall be fully and finally acquitted, and sin abolished for ever. 2. If we say, We have not sinned, we make him a liar, and his word is not in us,1 John 1:10. The denial of our sin not only deceives ourselves, but reflects dishonour upon God. It challenges his veracity. He has abundantly testified of, and testified against, the sin of the world. And the Lord said in his heart (determined thus with himself), I will not again curse the ground (as he had then lately done) for man's sake; for (or, with the learned bishop Patrick, though) the imagination of man's heart is evil from his youth,Genesis 8:21. But God has given his testimony to the continued sin and sinfulness of the world, by providing a sufficient effectual sacrifice for sin, that will be needed in all ages, and to the continued sinfulness of believers themselves by requiring them continually to confess their sins, and apply themselves by faith to the blood of that sacrifice. And therefore, if we say either that we have not sinned or do not yet sin, the word of God is not in us, neither in our minds, as to the acquaintance we should have with it, nor in our hearts, as to the practical influence it should have upon us.

_ _ II. The apostle then instructs the believer in the way to the continued pardon of his sin. Here we have, 1. His duty in order thereto: If we confess our sins,1 John 1:9. Penitent confession and acknowledgment of sin are the believer's business, and the means of his deliverance from his guilt. And, 2. His encouragement thereto, and assurance of the happy issue. This is the veracity, righteousness, and clemency of God, to whom he makes such confession: He is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness,1 John 1:9. God is faithful to his covenant and word, wherein he has promised forgiveness to penitent believing confessors. He is just to himself and his glory who has provided such a sacrifice, by which his righteousness is declared in the justification of sinners. He is just to his Son who has not only sent him for such service, but promised to him that those who come through him shall be forgiven on his account. By his knowledge (by the believing apprehension of him) shall my righteous servant justify many,Isaiah 53:11. He is clement and gracious also, and so will forgive, to the contrite confessor, all his sins, cleanse him from the guilt of all unrighteousness, and in due time deliver him from the power and practice of it.

1 John 1:8

If we say  Any child of man, before his blood has cleansed us. We have no sin  To be cleansed from, instead of confessing our sins, 1 John 1:9, the truth is not in us  Neither in our mouth nor in our heart.

1 John 1:8

(5) If we say that we have no sin, we (e) deceive ourselves, and the (f) truth is not in us.

(5) There is none but need this benefit, because there is none that is not a sinner.

(e) This fully refutes that perfectness of works of supererogation (doing more than duty requires, the idea that excess good works can form a reserve fund of merit that can be drawn on in favour of sinners) which the papists dream of.

(f) So then, John speaks not thus for modesty's sake, as some say but because it is so indeed.

say:

1 John 1:6If we say that we have fellowship with him, and walk in darkness, we lie, and do not the truth:1 John 1:10 If we say that we have not sinned, we make him a liar, and his word is not in us.1 John 3:5-6 And ye know that he was manifested to take away our sins; and in him is no sin. ... Whosoever abideth in him sinneth not: whosoever sinneth hath not seen him, neither known him.1 Kings 8:46If they sin against thee, (for [there is] no man that sinneth not,) and thou be angry with them, and deliver them to the enemy, so that they carry them away captives unto the land of the enemy, far or near;2 Chronicles 6:36 If they sin against thee, (for [there is] no man which sinneth not,) and thou be angry with them, and deliver them over before [their] enemies, and they carry them away captives unto a land far off or near;Job 9:2 I know [it is] so of a truth: but how should man be just with God?Job 14:4Who can bringa clean [thing] out of an unclean? not one.Job 15:14 What [is] man, that he should be clean? and [he which is] born of a woman, that he should be righteous?Job 25:4How then can man be justified with God? or how can he be clean [that is] born of a woman?Psalms 143:2 And enter not into judgment with thy servant: for in thy sight shall no man living be justified.Proverbs 20:9 Who can say, I have made my heart clean, I am pure from my sin?Ecclesiastes 7:20 For [there is] not a just man upon earth, that doeth good, and sinneth not.Isaiah 53:6All we like sheep have gone astray; we have turned every one to his own way; and the LORD hath laid on him the iniquity of us all.Isaiah 64:6 But we are all as an unclean [thing], and all our righteousnesses [are] as filthy rags; and we all do fade as a leaf; and our iniquities, like the wind, have taken us away.Jeremiah 2:22-23For though thou wash thee with nitre, and take thee much soap, [yet] thine iniquity is marked before me, saith the Lord GOD. ... How canst thou say, I am not polluted, I have not gone after Baalim? see thy way in the valley, know what thou hast done: [thou art] a swift dromedary traversing her ways;Romans 3:23 For all have sinned, and come short of the glory of God;James 3:2 For in many things we offend all. If any man offend not in word, the same [is] a perfect man, [and] able also to bridle the whole body.

we deceive:

1 Corinthians 3:18 Let no man deceive himself. If any man among you seemeth to be wise in this world, let him become a fool, that he may be wise.Galatians 6:3 For if a man think himself to be something, when he is nothing, he deceiveth himself.2 Timothy 3:13 But evil men and seducers shall wax worse and worse, deceiving, and being deceived.James 1:22 But be ye doers of the word, and not hearers only, deceiving your own selves.James 1:26 If any man among you seem to be religious, and bridleth not his tongue, but deceiveth his own heart, this man's religion [is] vain.2 Peter 2:13 And shall receive the reward of unrighteousness, [as] they that count it pleasure to riot in the day time. Spots [they are] and blemishes, sporting themselves with their own deceivings while they feast with you;

the truth:

1 John 2:4 He that saith, I know him, and keepeth not his commandments, is a liar, and the truth is not in him.1 Timothy 6:5 Perverse disputings of men of corrupt minds, and destitute of the truth, supposing that gain is godliness: from such withdraw thyself.2 John 1:2 For the truth's sake, which dwelleth in us, and shall be with us for ever.3 John 1:3 For I rejoiced greatly, when the brethren came and testified of the truth that is in thee, even as thou walkest in the truth.